From: Xiongwei Song <sxwjean@me.com>
To: peterz@infradead.org, mingo@redhat.com, will@kernel.org,
longman@redhat.com, boqun.feng@gmail.com
Cc: linux-kernel@vger.kernel.org, Xiongwei Song <sxwjean@gmail.com>
Subject: [PATCH 3/3] locking/lockdep: print possible warning after counting deps
Date: Thu, 17 Jun 2021 22:28:28 +0800 [thread overview]
Message-ID: <20210617142828.346111-4-sxwjean@me.com> (raw)
In-Reply-To: <20210617142828.346111-1-sxwjean@me.com>
From: Xiongwei Song <sxwjean@gmail.com>
The graph walk might hit error when counting dependencies. Once the
return value is negative, print a warning to reminder users.
Suggested-by: Waiman Long <longman@redhat.com>
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
---
kernel/locking/lockdep.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index cb94097014d8..cfe0f4374594 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -2028,8 +2028,12 @@ static unsigned long __lockdep_count_forward_deps(struct lock_list *this)
{
unsigned long count = 0;
struct lock_list *target_entry;
+ enum bfs_result ret;
+
+ ret = __bfs_forwards(this, (void *)&count, noop_count, NULL, &target_entry);
- __bfs_forwards(this, (void *)&count, noop_count, NULL, &target_entry);
+ if (bfs_error(ret))
+ print_bfs_bug(ret);
return count;
}
@@ -2053,8 +2057,12 @@ static unsigned long __lockdep_count_backward_deps(struct lock_list *this)
{
unsigned long count = 0;
struct lock_list *target_entry;
+ enum bfs_result ret;
+
+ ret = __bfs_backwards(this, (void *)&count, noop_count, NULL, &target_entry);
- __bfs_backwards(this, (void *)&count, noop_count, NULL, &target_entry);
+ if (bfs_error(ret))
+ print_bfs_bug(ret);
return count;
}
--
2.30.2
next prev parent reply other threads:[~2021-06-17 14:29 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-17 14:28 [PATCH 0/3] some improvements for lockdep Xiongwei Song
2021-06-17 14:28 ` [PATCH 1/3] locking/lockdep: unlikely bfs_error() inside Xiongwei Song
2021-06-17 14:28 ` [PATCH 2/3] locking/lockdep: unlikely conditons about BFS_RMATCH Xiongwei Song
2021-06-17 14:28 ` Xiongwei Song [this message]
2021-06-17 15:12 ` [PATCH 3/3] locking/lockdep: print possible warning after counting deps Boqun Feng
2021-06-18 1:54 ` Xiongwei Song
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